Question, is this just for in-game or wifi play? Since you're not really sure on items and haven't ev'd Pokemon, it's not really clear whether it is or not. :x Just going to make a few little comments anyway; it'd also be useful if you included your abilities, too, for everything and not just Crustle.

Either way, yes, Gliscor does need Adamant, since the set you're using relies on attack, and generally with acrobatics, you go with flight gem as the item for the initial boost in power. While ice fang can work on normal sets (and there's no reason it can't on the acrobats BUT) substitute is generally the preferred option there - though I've found taunt can still work well on this set too. You'd invest in attack/speed, anyway.

Since you're going for a defensive Empoleon, best to go with leftovers as an item so you can last long - generally your only issue is WOULD have been toxic, but since you're steel it's not really an issue, aka it allows you to recover or at least stay around the same even if you're burned. Also generally Empoleon runs with Stealth Rock on that set, though Grass Knot/Ice Beam can work as two. In which case you'd go with a Calm nature, investing in spD and HP.

Also on Crustle, I'd go with Stone Edge > Rock Slide since generally I prefer the chance of critting and higher power rather than higher accuracy and lower power. :x Also on Crustle you can go with either Life Orb for power - or Expert Belt, up to you.